Microvariable paper machine drive



Oct. 29, 1940. M. T. WESTON 2,219,856

MICROVARIABLE PAPER MACHINE DRIVE I Filed Aug. 19, 1956 3 Sheets-Sheet lYJU Oct. 29, 1940. M. T. WESTON MICROVARIABLE PAPER MACHINE DRIVE FiledAug. 19. 1936 3 Sheets-Sheet 2 k I I I u f,

I 0.0. a I000 IN VENTOR Oct. 29, 1940. M. T. WESTON MICROVARIABLE PAPERMACHINE DRIVE Filed Aug. 19. 1936 3 Sheets-Sheet 5 IN VlfNTU/f PatentedOct. 29, 1940 UNITED STATES PATENT 'oFFicE 2,219,856 MICROVARIABLE PAPERMACHINE DRIVE Application August 19, 1986, Serial No. 96,805 4 Claims.v(Cl. 34-48) My invention relates to improvements in microvariable papermachine drives and has particular reference to the method of driving thedrier section of the paper machine. The present practice is topositively gear all of the drier cylinders in the section together sothat the peripheries of all of the cylinders have exactly the samevelocity. On account of the snubbing action of so many cylinders, andfurther because the tension in the felts holds the paper web firmlyagainst the surfaces of the drier cylinders, there can be no slipping ofthe paper web to allow for the normal shrinkage which, in a modernmachine, is very considerableprobably as much as 10 to feet between thefirst and last drier cylinder. The effect is, in reality, the stretchingof the paper web to this extent in the machine direction and causing anabnormal shrinkage in the cross direction. This stretch- 0 ing of thepaper results in a pronounced orientation of the fibers in the machinedirection at the expense of the cross direction, making the paper muchstronger in the one direction thaiT in the other. Repeated tests haveshown that the prevention of the normal shrinkage of the paper webproduces a sheet 2 times stronger in the machine direction than in thecross direction-a very undesirable result. Other tests have proven thatmost of the fiber orientation in the present 0 system occurs at thedrier section. If this orientation of the fibers in the. machinedirection can be prevented by allowing the paper web to shrink normally,a condition will result wherein the paper web will be more nearly equalin strength in both directions-a most desirable result.

The principal object of my invention is to provide a microvariablemechanism which is capable of extremely fine adjustments by almostinfinitesimal increments, independent of the rotational speeds at whichthe drive is operating. My microvariable drive, therefore, makes itpossible to,

obtain the required fineness of adjustment necessary to provide aprogressive difference in peripheral speeds of the several driercylinders, from the first to the last, to allow for the proper shrinkageof the paper web and thus prevent orientation of the fibers in themachine direction. Other objects are simplicity in construction andoperation and economy in manufacture. Further objects will appear in thefollowing specification and are shown in the accompanying drawings inwhich similar reference numerals refer to like parts in all of theviews.

Fig. 1 is a vertical cross sectional view of one embodiment of myinvention and is taken on a line I-l of Fig. 4.

Fig. 2 is a detail view of a modification in the hub arrangement.

Fig. 3 is a detail sectional view of the rim in Fig. 1 showing thetapered rings in a different relation.

Fig. 4 is a side elevation of the embodiment of my invention shown inFig; 1.

Fig. 5 is a partial side elevation of another embodiment of myinvention. In this view the flanged ring at the right of Figs. 6 and 7is.omitted to show the construction more clearly.

Fig. 6 is a sectional view of the rim and is taken-on a line 66 of Fig.5.

Fig. 7 is a sectional view of the rim and is taken on a line 1-7 of Fig.5.

Fig. 8 is a diagrammatic view intended to illustrate the operation ofthe embodiment of my invention shown in Figs. 1 and 4. t

Fig. 9 is a diagrammatic view illustrating the use of silent chain inconnection with the embodiment shown in Figs. 5, 6 and 7. r

Fig. 10 is a diagrammatic view illustrating the use of gears inconnection with the embodiment 25 shown in Figs. 5, 6 and 7.

In the drawings, I is the shaft on which a drier cylinder 2 isrevolvably mounted. .A spider or hub member 3 constituting a drivereceiving member is keyed on the end of the shaft l and 3 has a plainrim 4 on which are mounted the axially slidable steel rings 5 havingoppositelytapered faces. Mounted in pockets 6 in the rim 4 are theaxially parallel shafts I revolvable in and held against axial movementby the bearing 5 bosses 8 in the pockets 6. These shafts are threadedright and left hand on either side of the bearing bosses 8 and one endof each shaft 1 projects outwardly and carries a worm wheel 9 keyed on.On the inner peripheries of the ta- 40 pered rings 5 are securely fixedthe threaded lugs It] in positions registering with the threadedsections of the shafts 1. Clearly the simultaneous rotation of theshafts 1 will cause the two tapered rings 5 to move axially on the plainrim 45 4 either toward or away from each other dependin'gpupon thedirection of rotation of the shafts I. Meshing with warm wheels 9 arethe worms II mounted in operating relation on the shafts l2 extendingsomewhat radially toward 5 the center and on the inner ends of theseshafts I 2 are secured the Worm wheels l3 which mesh with a worm 14common to all of them. In Figs. 1 and 4 this worm I4 is shown integralwith a sleeve l5 while in Fig.2 it is regular. 55

- In drier cylinders on paper machines it is necessary to provide steam'for heating and also means for removing the condensate, usually thruthe hollow end of the drier shaft I. this by providing a tube l6 whichis firmly secured in the hollow end of the shaft I and which extendsoutwardly and terminates in a fixed casting l1. Steam is brought to thiscasting thru pipe l8 and the condensate is removedthru pipe l9.

The construction is regular and therefore the details are not shown.

In Figs. 1, 4 and I show a housing 20, at-

tached to the face of the hub of the hub mem-- quire heating, such asthe upper press rolls of paper machines, the. motor mounting shown inFig. 2 may be used. Here a standard flanged motor 26 is attached to thehouseing and a standard worm 21 is mounted on the armature shaft inproper position to mesh with the central worm wheels i3.v Current isbrought to the revolving motor 26 thru wiring and the usual collectorrings 28. p The foregoing embodiment .of my invention contemplates theuse of my driving chain as covered by my U. S. Patent No. 1,997,284dated April 9, 1935, which will operate on an infinite number of pitchdiameters and is designed to run on the tapered rings 5. Fig. 8illustrates the operation as follows. The tapered rings 5 0 on my unitdriving the first drier cylinder are widely separated, as in Fig. 1,which allows the chain 29 to run on a pitch diameter toward the bases ofthe rings-practically the minimum pitch diameter. At each succeedingdrier cylin- 45 der the rings 5 are moved toward each other by extremelysmall increments by running the motors successively for a limited timewhich has the effect of progressively slowing down the drier cylindersjust enough to allow for the proper 50 shrinkage of the paper web. Theposition of the chain at the last drier cylinder at the right of Fig. 8,and as illustrated in Fig. 3, is toward the outer periphery of the rings5 which have moved to their closest positions, thus causing the chain 55to run on its maximum pitch diameter at which time the correspondingdrier cylinder is running at its slowest speed relative to the precedingcylinders. In practice the difference between the minimum and maximumpitch diam- 60 eters will be sufficient to provide for the greatestamount of shrinkage in the paper web that may occur at the drier sectionof the paper machine.

Any desired pitch diameter, of the infinite number available, isobtained and maintained by 5 simply stopping the motor when that pitchdiameter is reached.

In order to make it possible to use a driving chain of standard make, Ishow a modification in the rim design in Figs. 5, 6 and 7. Instead of 70the tapered rings 5 I use an annular ring 30 having sprocket teethon'its outer periphery and gear teeth on its inner periphery. This ring30 is revolvable on the rim 4a which has an annular recess 32 toaccommodate the internal 7 teeth. One flange 33 is removable to permit Iaccomplish using aspeed motors and 26. The higher the motor speed thegreater the amount of variation obtained. The progressive variation inthe successive drier cylinders is therefore obtained by operating eachof the several motors progressively at a slightly higher speed than thepreceding one.

Similarly, we may regard the teeth on the outer periphery of theannularring as gear teeth which may mesh with the teeth on annular rings inadjacent units as shown in Fig. 10. each of the drier cylinders equippedwith my microvariable unitis operating at a slightly reduced speed withrespect to the preceding one, there can be no snubbing action and thepaper web will be free to shrink proportionately between any two of thelower cylinders driven by my microvariable units. In practice the chain36, Fig. 9, is driven by drive pinion 31 at a speed 'which is properlyrelated to the other parts of a papermaking machine as is customary inthe art. In Fig. 10 the gear train, comprising the gears 30, is drivenby pinion 38. Similarly the chain 29 of Figs, 1, 3 and 8 is driven by adriving sheave, not shown.

The operation of my invention has been made clear in the foregoing. Theextremely fine adjustments required to allow for the relatively smallshrinkage of the paper web between any two adjacent drier cylinders ismade possible in applicant's microvariable mechanism by the compoundingof mechanical elements having very high speed-reducing characteristics.

Claims to the arrangement according to Figs. 5, 6 and 7 are made in mycopending application Serial No. 183,745 filed January 'I, 1938.

Having thus described my invention I claim as new and desire to secureby Letters Patent:

1. In a nest of positively driven paper drier cylinders, supportingshafts or trunnions for said ,cylinders, co-axial drive receivingmembers respectively secured to said cylinders for the purpose ofdriving same and including a pair of opposed, tapered sheave membersadapted to receive between them a drive chain, a drive chain for drivingthe cylinders of the nest through said members, said sheave members ofat least some of said drive receiving members being capable ofsimultaneous movement toward and away from each other by equalincrements, screw devices for accomplishing said movement, and means foractuating said screw devices comprising a driven member concentric withits drier cylinder, driving means for said driven member and a pluralityof. drive shafts operatively connecting said driven member with saidscrew devices whereby the effective diameter of such drive receivingmember can be varied to produce minute variations in speed of a cylinderto which it is connected to compensate for shrinkage of the paper indrying a 2. The combination of elements according to claim 1 includingmeans for heating said cylinders.

3. The combination ofelements according to Since claim 1 in which saiddriven member is comprised o! a sleeve, such combination of elementsfurther including a. pipe passing through said sleeve for introducingheating fluid within the drying cylinder. 7

MILTON 'T. WESTON. 5

